Under Your Skin:

What
You Donít Know About Dermal Exposures Can Make You Sick

Imagine trying to shield your
workers from air-borne chemicals without the benefit of air monitors,
permissible exposure limits, ventilation designs, or certified, fit-tested
respirators. No way to detect noxious fumes. No values by which to gauge safe
levels. No assurance that workersí equipment is actually protecting them. Talk
about making your job difficult! Respiratory protection would be near
impossible. Yet this is just what youíre up against trying to detect and
control hidden hazards that get at workers through their skin.

More than 100 chemicals with OSHA
permissible exposure limits for inhalation hazards are also known skin permeants. Like the effects of breathing toxic fumes, when one of these
substances is absorbed into the blood stream through the skin, the result can
be serious; kidney or liver disease, neurological or reproductive disorders,
or cancer.

For instance, about a teaspoonful
of styrene (3 milliliters) splashed on a workerís skin can deliver the same
dose as the eight-hour inhalation exposure limit-50 parts per million. Just
touching a surface contaminated with 1.5 micrograms per square centimeter of
the suspected carcinogen acrylamide (a quantity about one-millionth the weight
of a paper clip) could equal inhaling one dayís permissible exposure limit,
0.03 milligrams per cubic meter.

But other than a "skin
notation" alongside the PEL for permeating chemicals, OSHA offers nothing
to help safety and health pros trying to deal with dermal exposures. No limits
tell you how much of a chemical can safely contact workersí skin. And even if
skin exposure levels were established, no tool like an air monitor exists to
measure them.

Likewise, no NIOSH standard, like
the one the agency recently updated for respiratory protective equipment,
exists to help managers sort through the variety of glove materials available.

NIOSH researcher Mark Boeniger
calls the inattention to dermal exposures "one of the greatest failures
of OSHA and NIOSH." Other skin experts accuse universities of contributing
to the problem by glossing over dermal absorption when training young health
and safety professionals.

"If you talk to 100
industrial hygienists, 95 percent of them will know what their plantís airborne
exposures are," says dermal absorption expert Tom Klingner. "But ask
them whether theyíre protecting workers from dermal exposures and they have no
idea." Industrial hygiene graduate students have told Klingner they
learned more about dermal exposures during a half-hour conversation with him
than they did during their grad school career.

The price of ignorance is that
many workers are left with only Mother Natureís thin line of defense. Little
more than their skins own stratum corneum (a protective layer no thicker than a
strand of hair) comes between them and the toxics they touch. Whatís worse is
that some common ways to protect skin such as wearing gloves, applying barrier
creams, and scrubbing clean after work doesnít always do the job. In fact, they
can raise the risks of dermal absorption.

Thereís no question industry needs
help protecting workersí skin. The health effects of dermal absorption are so
difficult to trace and can take so long, sometimes a lifetime to detect, that
illness data is impossible to collect. OSHA doesnít know how many people are exposed
to skin permeating chemicals at work. But the fact that dermal diseases and
disorders like dermatitis were long the most often reported job illness in the
U.S., only recently displaced by cumulative trauma disorders, indicates that
skin protection is overlooked in more than a few workplaces.

Detecting Dermal Exposures

Until NIOSH findings, EPA data
gathering, or OSHA standards offer any real guidance, youíre on your own. Your
task is indeed daunting: dermal dangers can be as obvious as a chemical splash
on a torn glove, or as inconspicuous as contaminated safety glasses rubbing the
thin skin behind the ears.

Just getting workers to comprehend
dermal absorption can be difficult. Inhalation exposures are easy enough to
understand. Everyone knows a sneeze can pass a cold through the air. Most
people recognize the dangers of breathing cigarette smoke. So itís not a
stretch to make the case that chemical contaminated air can be bad for you. But
good luck convincing a worker that holding a carbon disulfide contaminated tool
in a bare hand day after day can damage his sperm.

Tom Klingner recalls the irony of
watching a gardener spray pesticides on flowers outside an industrial
hygienistsí convention in Anaheim, Cal., two years ago. "The guy wore hip
boots and gloves while he sprayed. When he was done, he went to his truck,
pulled off a glove, and then yanked off the other glove and both boots with his
bare hands." Providing protective clothing isnít enough, Klingner says.
Educating workers and changing their behavior is the other half of the battle.

Trickier still can be the task of
tracking the source when employees are dermally exposed. In the poly-urethane
industry, where the suspected bladder carcinogen methylene bischloro aniline (MOCA) is a common hazard, the Polyurethane Manufacturers Association has long
supported voluntary urine monitoring to detect exposures. Klingnerís firm,
Colormetric Laboratories in Des Plaines, Ill., runs urine tests for several
polyurethane clients who he says have "set the standard for all
industries." Consider a few of his sleuthing stories:

Urine tests at a California
maker of cast polyurethane wheels (typical in childrenís in-line skates)
revealed that office workers were suffering MOCA exposures. Traces of the
chemical appeared in the urine of secre-taries who never stepped near the
manufacturing floor. Surface swipes identified the source: paperwork.
Workers in the plant who signed paperwork with contaminated gloves passed
along the MOCA to the front office.

At another plant, Klingner
was puzzled to find that among maintenance workers tested for MOCA
exposures, the two with the highest exposures didnít even work in
contaminated areas. Eventually he discovered they were snitching, with
their bare hands, tools from the contaminated toolbox of a co-worker whose
exposure level was much lower, and who always wore gloves.

An employee whose job at
another cast polyurethane plant was to meter material out of a mixing head
and hand pour it into molds changed from street clothes into protective
clothing before work. When tests showed high exposure levels, Klingner
discovered the workerís boots had been splashed with chemicals. The man
was contaminating himself every morning pulling on his boots, and
compounding the problem by wearing gloves over his dirty hands all day.

Solutions for these cases were
simple: encase paperwork in plastic folders that get removed before passing
along from the plant to the office; paint tools used in contaminated areas red
as a warning to don gloves; and keep reusable PPE clean and use disposable shoe
covers for chemical splashes. The real challenge is educating workers to
prevent the exposures in the first place.

These dos and doníts can help
minimize risks to the skin:

Do:

Keep skin clean and
healthy. Abraded, irritated, or even sun burnt skin is more susceptible to
dermal absorption. Use products tailored to the industrial market, not just cosmetic moisturizers, says
EleanorFendler, Ph.D., product
developmentmanager for skin care company
GojoIndustries.

Keep hands and skin dry.
Moisture on the skin, like sweat, can enable permeation, as can high
temperatures.

Choose gloves and
protective materials carefully. Some chemicals, like lacquer thinner, can
permeate just about any glove when microscopic molecules break through
individual molecules of the protective film on the glove. But beware, too,
of over protecting. A glove that is too thick or bulky only contributes to
exposure risks when workers remove it to perform jobs requiring dexterity
or tactility.

Watch out for glove
degradation. Donít rely on a glove once its physical property changes,
says Nelson Schlatter of glove maker Ansell Edmont. "Degradation is
easy to spot," he says. "The glove will either swell up and get
soft, or shrink and harden." Flexing a glove can increase the
permeation rate and breakthrough time by ten, according to NIOSHís
Boeniger. And, of course, chemicals can penetrate visible holes in gloves.

Donít:

Donít use solvents to clean
chemicals off hands. Solvents can damage the skin, making it more readily
permeable, says Fendler.

Donít put gloves on
contaminated hands. Gloves can force penetration of chemicals already on
the hands and increase the likelihood of dermal penetration up to five
times, according to Boeniger.

Donít apply moisturizer or barrier cream
to contaminated skin. "If an auto mechanic puts barrier cream on his
hands after he changes the oil, he can be causing himself really serious
damage by forcing penetration," Fendler says.

Donít use barrier
creams in the place of gloves. Barrier creams can be an addition to a skin
protection regime, but studies recommend against substituting them for gloves.